Oscar-winning documentarian Alex Gibney has become the film world's chief reporter on the abuse of power. His first major documentary, "Enron: The Smartest Guys in the Room," chronicled how the business became the face of white-collar corruption. Two years later, he won his Oscar for "Taxi for the Dark Side," the story of an Afghan taxi driver tortured to death in the earliest days of the Iraq War and an indictment of the U.S.'s torture tactics.

Now, Gibney turns his camera toward the Vatican and the priest sex abuse scandal that sickened the public and tainted many's image of the powerful institution of the Catholic Church. The results, "Mea Maxima Culpa: Silence in the House of God," are riveting, horrifying, revolting and heartbreaking.

It also results in perhaps the most important movie you'll watch all year.

Gibney's film focuses in on a group of four young deaf Milwaukee boys in 1972. The boys go to St. John's School for the Deaf in St. Francis and love it there. That is, until the school's charismatic and beloved priest, Father Lawrence Murphy, begins sexually abusing the young men and over 200 others who were under his protective watch at the school.

The boys – whose grown-up selves tell their story to Gibney's camera with the help of sign language and celebrity voiceovers – are confused and appalled by Murphy's actions, but they continue to happen. After all, he is a priest; they trust him, and so did all of the nuns who worked at St. John's. Eventually, however, the men realize what has happened to them and join their powerful stories together to bring down Murphy.

By that time, more stories are coming out across the globe – namely Boston and Ireland in the film – about priests committing sexual abuse and receiving no punishment from either the church or the police. Throughout the course of the film, Gibney breaks down these cases, shows the disregarded attempts to contact church authorities and the chillingly devious cover-ups that imply that "as long as it's secret, it's okay."

"Mea Maxima Culpa" is a scathing and gripping attack on a system of unquestioned power that invites abuse by doing nothing to stop it. Many priests and Church officials close to the cases, in fact, ended up promoted to higher and better positions despite their inability to act. One Irish Church official notes that he didn't stop or investigate into the continuous abuse done by convicted priest Tony Walsh because "he had so much to do." Gibney also talks to several sources throughout the film who discuss the apparent lie of priest celibacy and the self-created organizations and investigations within the church to rehabilitate and cope with abusive priests.

Meanwhile, the victims are left looking for justice and receiving little understanding from others. When a man abused by Fr. Murphy confronts the priest at his house many years later, Murphy's housekeeper keeps questioning the man's religious devotion. Their "good faith" is supposed to explain away whatever wrongdoing occurred.

It should be noted that "Mea Maxima Culpa" is not an attack on the religion itself. It's goal is not to shake one's religious ideals but to expose the grave errors made by the human institution of the Church and the serious issues that arise when absolute control is allowed to reign. The film isn't questioning one's faith in God; it's questioning one's faith in humanity when they allow power to taint their morals.

Gibney's film contains gallons of information on the scandal, but thankfully, "Mea Maxima Culpa" never feels like an information dump. It substantive, but it never allows the facts to overwhelm the haunting human tragedy that occurred. It's almost impossible not to cry when one of the abused men heartbreakingly erupts in a letter to Murphy, filled with deep-seeded pain and sadness. In the end, Gibney creates one of the year's most informative but also emotional movies of the year.

The documentarian also powerfully allows his deaf subjects to tell their story. The audience can't hear their voices, but they can feel the men's quiet rage. I originally wasn't sure about the use of the celebrity voices for the voiceover. Ethan Hawke and "Mad Men"'s John Slattery do very well, but Chris Cooper's voice is so distinct that, for a few brief moments, it was distracting. As the film goes along, however, it becomes less of a hindrance and doesn't take away anything from the men's story.

Besides that, it's a superb, impeccably made documentary, organized to a T and remarkably honest.

No matter what one's religious beliefs and affiliations may be, "Mea Maxima Culpa" demands to be seen and heard. It reaches through the screen, grabs the audience and shakes them, the effects of which can be felt long after walking of the theater. The movie doesn't ask for justice; it screams for it. By the end of the film, you'll probably be joining in.

"Mea Maxima Culpa: Silence in the House of God" screens Friday, Oct. 5 at 7 p.m. at the Oriental Theatre as part of the 2012 Milwaukee Film Festival.